PSU · certified grade · default condition
PSU Medical Grade
Properties of the Medical Grade condition, compared with the other PSU grades.
Choose for reusable surgical trays, sterilization cases and fluid-handling devices needing biocompatibility documentation and 1000+ steam cycles.
What is PSU Medical Grade?
PSU Medical Grade is PSU in a Medical Grade certified grade — choose for reusable surgical trays, sterilization cases and fluid-handling devices needing biocompatibility documentation and 1000+ steam cycles. PSU Medical Grade has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 70 MPa (10.2 ksi) — stronger than 77% of polymer grades. Elongation at break is 55% and the elastic modulus is 2.5 GPa (0.363 Msi). PSU Medical Grade has a density of 1.24 g/cm³ (0.0448 lb/in³), heavier than 63% of polymer grades. Its glass-transition temperature is 185°C (365 °F).
Advantages
- High service temperature — 150°C (302 °F), better than 78% of polymer grades
- Polishes to a fine finish — 70/100, better than 78% of polymer grades
- High strength — 70 MPa (10.2 ksi), better than 77% of polymer grades
- Conducts heat well — 0.26 W/m·K (0.15 BTU/hr·ft·°F), better than 76% of polymer grades
Limitations
- High embodied carbon — 7 kg CO₂/kg, worse than 77% of polymer grades
PSU Medical Grade properties
Typical room-temperature values for PSU Medical Grade — 9 properties are specific to this condition; the rest are grade-level values shared by every PSU grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.
Physical6
PSU Medical Grade has a density of 1.24 g/cm³ (0.0448 lb/in³), heavier than 63% of polymer grades. Its glass-transition temperature is 185°C (365 °F).
Mechanical15
PSU Medical Grade has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 70 MPa (10.2 ksi) — stronger than 77% of polymer grades. Elongation at break is 55% and the elastic modulus is 2.5 GPa (0.363 Msi).
Thermal11
PSU Medical Grade is rated for continuous service to 150°C (302 °F). It conducts heat at 0.26 W/m·K (0.15 BTU/hr·ft·°F), better than 76% of polymer grades. Thermal expansion is 56 µm/m·K (31.1 µin/in·°F).
Electrical7
PSU Medical Grade is an electrical insulator with a dielectric strength of 17 kV/mm (431.8 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (80/100), worse than 55% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of PSU Medical Grade takes about 130 MJ of energy and emits 7 kg of CO₂ — more than 78% of polymer grades. Typical recycled content is 0%.
Manufacturability8
PSU Medical Grade's machinability is good (65/100, better than 66% of polymer grades); weldability good (60/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other PSU grades and fills
PSU is also supplied in 8 other conditions. The full side-by-side table is on the PSU overview.
- Medical GradeDefaultChoose for reusable surgical trays, sterilization cases and fluid-handling devices needing biocompatibility documentation and 1000+ steam cycles.70 MPa tensile
- CF30Polysulfone compounded with 30% short carbon fiber for maximum stiffness, dimensional stability and static-dissipative behaviour at up to ~160 °C.155 MPa tensile
- GF40Highly filled 40% short-glass polysulfone for maximum stiffness, creep resistance and low thermal expansion in electrically insulating structural parts.130 MPa tensile
- GF30Highest stiffness/creep resistance and lowest CTE of the PSU family; opaque, more abrasive to tools and molds.117 MPa tensile
- GF20Mid-level stiffening with lower warpage than GF30; use for load-bearing housings at 120–150 °C.100 MPa tensile
- UnfilledStandard injection/extrusion grade: pick for transparency, autoclavability and general high-temperature insulating parts.71 MPa tensile
- EXT-STOCKPick when parts are machined from semi-finished stock; annealed shapes minimize stress crazing and post-machining distortion.70 MPa tensile
- PTFE-LUBUse for sliding/wear parts needing low friction at high temperature; strength and ductility drop versus natural PSU.55 MPa tensile
Working with PSU Medical Grade
Is PSU easy to machine?
Machines like a tough amorphous plastic: sharp positive-rake carbide tools, high speed, light feed, air or water-soluble coolant only (avoid ketone/chlorinated cutting fluids); anneal blanks ~165 °C to relieve stress and prevent crazing.
Can PSU be welded?
Joins well by ultrasonic, hot-plate/hot-gas and spin welding; solvent bonding with methylene chloride blends is fast but leaves stress-crack risk, so epoxy or ultrasonic is preferred for medical parts.
Can PSU be formed, bent or molded?
Dry resin 3–4 h at 135–150 °C to <0.05% moisture, mold at 330–385 °C melt with 100–160 °C tool, moderate-high injection pressure; thermoformable and extrudable, shrinkage ~0.6% natural / ~0.2% GF30.
What surface finishes work on PSU?
Transparent grade can be flame- or vapor-polished and buffed to optical clarity; paints/adhesives need degreasing or plasma/corona activation; can be metallized or vacuum-sputtered, but unprotected surfaces yellow in sunlight.
PSU chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| bisphenol A (BPA) monomer unitpolycondensation with DCDPS forms the polysulfone backbone | ≈ 45 | 45 |
| 4,4'-dichlorodiphenyl sulfone (DCDPS) moaryl-ether-sulfone repeat unit -[O-C6H4-C(CH3)2-C6H4-O-C6H4-SO2-C6H4]- | ≈ 55 | 55 |
| glass fiberonly in GF variants (sized chopped E-glass) | 10 – 30 | 30 |
| PTFEonly in lubricated bearing grades | 10 – 15 | 15 |
| polysulfone polymernatural grade is 100% polymer; no filler, minimal additives | balance | — |
PSU Medical Grade — frequently asked
What is PSU Medical Grade used for?
PSU Medical Grade is typically used for medical instrument trays and sterilization cases, dialyzer housings and membranes, food-contact containers, hot-water pipe fittings, electrical insulating components and reusable autoclavable medical parts. In short: high-heat steam resistant.
What is the yield strength of PSU Medical Grade?
PSU Medical Grade has a typical yield strength of 70 MPa (10.2 ksi) and a tensile strength of 70 MPa (10.2 ksi) — stronger than 77% of polymer grades. Strength varies by condition: see the 9 listed tempers.
Is PSU Medical Grade easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Machines like a tough amorphous plastic: sharp positive-rake carbide tools, high speed, light feed, air or water-soluble coolant only (avoid ketone/chlorinated cutting fluids); anneal blanks ~165 °C to relieve stress and prevent crazing.
Can PSU Medical Grade be welded?
Yes — weldability is rated good (60/100). Joins well by ultrasonic, hot-plate/hot-gas and spin welding; solvent bonding with methylene chloride blends is fast but leaves stress-crack risk, so epoxy or ultrasonic is preferred for medical parts.
What surface finishes work on PSU Medical Grade?
Transparent grade can be flame- or vapor-polished and buffed to optical clarity; paints/adhesives need degreasing or plasma/corona activation; can be metallized or vacuum-sputtered, but unprotected surfaces yellow in sunlight.
Can PSU Medical Grade be formed, bent or molded?
Dry resin 3–4 h at 135–150 °C to <0.05% moisture, mold at 330–385 °C melt with 100–160 °C tool, moderate-high injection pressure; thermoformable and extrudable, shrinkage ~0.6% natural / ~0.2% GF30.
What is the maximum service temperature of PSU Medical Grade?
PSU Medical Grade is rated for continuous use to about 150°C (302 °F), and briefly to 180°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in PSU Medical Grade?
Yes — PSU Medical Grade is available for CNC machining, sheet metal and injection molding with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Udel PSU Design Guide & P-1700 data sheet — Solvay Specialty Polymers (2021)
- TECASON S (PSU) stock shapes datasheet — Ensinger (2022)
- CAMPUS plastics data – polysulfone (PSU) grades — CWFG / CAMPUS consortium (2023)
- Engineered Materials Handbook Vol.2: Engineering Plastics — ASM International (1988)
- ISO 527-2 / ISO 75 / ASTM D638, D790, D256, D257 test methods — ISO / ASTM (2019)
- GB/T 13527 / ISO 10993-1 biological evaluation reference for medical PSU — SAC / ISO (2018)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.